Project description:Innate immunity, the first line of host defense against pathogens, is tightly regulated both transcriptionally and post-transcriptionally. Through global transcriptome and proteome analyses in Caenorhabditis elegans, we uncover a modulation of the expression of secreted innate immunity effector proteins by TENT5, one of a recently described family of cytoplasmic poly(A) polymerases. Direct RNA sequencing revealed that TENT-5 polyadenylates mRNAs with signal peptide-encoding sequences, that are translated at the endoplasmic reticulum. Loss of tent-5 function makes worms more susceptible to bacterial infection. Importantly, we demonstrate that the function of TENT-5 in innate immunity is evolutionarily conserved, as its orthologs, TENT5A and TENT5C are induced during macrophage activation and polyadenylate mRNAs, some of which are of genes orthologous to C. elegans TENT-5 targets. In summary, our study reveals cytoplasmic polyadenylation to be a previously unknown component of the post-transcriptional regulation of innate immunity in animals.
Project description:Innate immunity, the first line of host defense against pathogens, is tightly regulated both transcriptionally and post-transcriptionally. Here, through global transcriptome and proteome analyses in Caenorhabditis elegans, we uncover a modulation of the expression of secreted innate immunity effector proteins by TENT5, one of a recently described family of cytoplasmic poly(A) polymerases. Direct RNA sequencing revealed that TENT-5 polyadenylates mRNAs with signal peptide-encoding sequences, that are translated at the endoplasmic reticulum. Loss of tent-5 function makes worms more susceptible to bacterial infection. Importantly, we demonstrate that the function of TENT-5 in innate immunity is evolutionarily conserved, as its orthologs, TENT5A and TENT5C are induced during macrophage activation and polyadenylate mRNAs, some of which are of genes orthologous to C. elegans TENT-5 targets. In summary, our study reveals cytoplasmic polyadenylation to be a previously unknown component of the post-transcriptional regulation of innate immunity in animals.
Project description:Cytoplasmic polyadenylation plays a vital role in gametogenesis, however, the participating enzymes and substrates in mammals remain unclear. Using knockout and knock-in mouse models, we describe the essential role of 4 TENT5 poly(A) polymerases in mice fertility and gametogenesis. TENT5B and TENT5C play crucial, but redundant roles in oogenesis, with double knockout of both genes leading to oocyte degeneration. Additionally, TENT5B-GFP females display gain-of-function infertility effect with multiple chromosomal aberrations in ovulated oocytes. TENT5C and TENT5D both regulate different stages of spermatogenesis, shown by sterility of males with either gene’s knockout mutation. Finally, Tent5a knockout significantly lowers fertility, although the underlying mechanism is not directly related to gametogenesis. Through Direct RNA sequencing we discovered that TENT5 proteins polyadenylate mRNAs encoding endoplasmic reticulum-targeted proteins essential for gametogenesis. Sequence motives analysis and reporter mRNA assay revealed that the presence of endoplasmic reticulum-leader represents the primary determinant of TENT5-mediated regulation.
Project description:Spatial regulation of mRNA polyadenylation is a key emerging mechanism shaping cellular function. The TENT5/FAM46 family comprises four non-canonical poly(A) polymerases that stabilize transcripts encoding ER-targeted proteins, with mutations linked to diseases of professional secretory cells. Using transcriptomic profiling coupled with systematic mutagenesis, we uncover how paralog-specific evolutionary divergence dictates distinct subcellular localization, interaction, and functional outcomes. TENT5D, the most ER-associated member, triggers widespread proteome remodeling, boosting the concerted expression of ER, ERGIC, Golgi, and lysosomal proteins. In contrast, TENT5B lacks ER targeting and regulates proteins involved in cell division. Mechanistically, a member-specific C-terminal region that binds ER-transmembrane FNDC3 proteins is necessary and sufficient for ER localization. Altogether, our findings reveal a domain-encoded mechanism linking TENT5 localization to transcript selectivity and secretory output. The TENT5–FNDC3 axis thus emerges as a key orchestrator of the cellular translatome and organelle identity.
Project description:Spatial regulation of mRNA polyadenylation is a key emerging mechanism shaping cellular function. The TENT5/FAM46 family comprises four non-canonical poly(A) polymerases that stabilize transcripts encoding ER-targeted proteins, with mutations linked to diseases of professional secretory cells. Using transcriptomic profiling coupled with systematic mutagenesis, we uncover how paralog-specific evolutionary divergence dictates distinct subcellular localization, interaction, and functional outcomes. TENT5D, the most ER-associated member, triggers widespread proteome remodeling, boosting the concerted expression of ER, ERGIC, Golgi, and lysosomal proteins. In contrast, TENT5B lacks ER targeting and regulates proteins involved in cell division. Mechanistically, a member-specific C-terminal region that binds ER-transmembrane FNDC3 proteins is necessary and sufficient for ER localization. Altogether, our findings reveal a domain-encoded mechanism linking TENT5 localization to transcript selectivity and secretory output. The TENT5–FNDC3 axis thus emerges as a key orchestrator of the cellular translatome and organelle identity.
2026-05-14 | GSE326742 | GEO
Project description:Insulin synthesis is sustained by Tent5 poly(A) polymerases
Project description:FAM46C is one of the most frequently mutated genes in multiple myeloma (MM) and encodes a protein of unknown function. Using a combination of in vitro and in vivo approaches, we demonstrate that FAM46C encodes an active cytoplasmic non-canonical poly(A) polymerase, which enhances mRNA stability and gene expression. Moreover, we also found that the reintroduction of active FAM46C into MM cell lines, but not its catalytically-inactive mutant, leads to broad polyadenylation and stabilization of mRNAs strongly enriched with those encoding endoplasmic reticulum-targeted proteins and induced cell death. This is, to our knowledge, the first report that directly associates cytoplasmic poly(A) polymerase with carcinogenesis. Furthermore, our data suggest that the human genome encodes at least eleven non-canonical poly(A) polymerases with four FAM46 family members. Since FAM46 proteins are differentially expressed during development, these proteins may positively regulate transcript stability and translational rate in a tissue-specific manner.
Project description:The bone formation, osteogenesis, is a very complex process in which osteoblasts play a crucial role. The primary function of theses terminally differentiated mesenchymal stem cells is the secretion of fibrillary, dense, highly crosslinked type 1 collagen. Herein we show that the TENT5A gene, which mutations lead to osteogenesis imperfecta, is an active cytoplasmic poly(A) polymerase, which in osteoblast positively regulates the expression of collagen subunits and also other secreted proteins essential for proper bone formation. TENT5A substrates have shorter poly(A) tails in TENT5 KO, as revealed by direct RNA sequencing. In the case of Col1α1 and Col1α2 transcripts, the lack of cytoplasmic polyadenylation by TENT5 leads to drastic decree in the protein production but also aberrant structure. The increase in TENT5A expressing during osteoblasts differentiation positively correlates with the cytoplasmic extension of the poly(A) trials of mRNA targets. The first physiologically relevant regulation of collagen expression at the posttranscriptional level.